Fair Value of Financial Instruments	12 Months Ended
Dec. 31, 2022
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	Fair Value of Financial Instruments Acquisition-Related Contingent Consideration and Other Liabilities Acquisition-related contingent consideration and other liabilities is composed of Earn-outs, which represent the estimated fair value of future amounts payable for businesses, including for mandatorily redeemable non-controlling interests, that are contingent upon the acquired business achieving certain levels of earnings in the future. As of December 31, 2022 and 2021, the estimated fair value of the Company’s Earn-out liabilities totaled $127.4 million and $160.2 million, respectively, of which $13.9 million related to mandatorily redeemable non-controlling interests as of both periods. Earn-out liabilities included within other current liabilities totaled approximately $37.7 million and $38.8 million as of December 31, 2022 and 2021, respectively. The fair values of the Company’s Earn-out liabilities are estimated using income approaches such as discounted cash flows or option pricing models, both of which incorporate significant inputs not observable in the market (Level 3 inputs), including management’s estimates and entity-specific assumptions, and are evaluated on an ongoing basis. Key assumptions include the discount rate, which was 12.0% as of December 31, 2022, and probability-weighted projections of earnings before interest, taxes, depreciation and amortization (“EBITDA”). Significant changes in any of these assumptions could result in significantly higher or lower potential Earn-out liabilities. The ultimate payment amounts for the Company’s Earn-out liabilities will be determined based on the actual results achieved by the acquired businesses. As of December 31, 2022, the range of potential undiscounted Earn-out liabilities was estimated to be between $38 million and $144 million; however, there is no maximum payment amount. Earn-out activity consists primarily of additions from new business combinations; changes in the expected fair value of future payment obligations; and payments. For the years ended December 31, 2022, 2021 and 2020, additions from new business combinations totaled approximately $2.8 million, $101.6 million and $7.2 million, respectively. Measurement period adjustments for the year ended December 31, 2022 totaled an increase, net, of approximately $3.3 million and related to a net increase in the Company’s Oil and Gas segment, partially offset by a decrease in its Communications segment. There were no measurement period adjustments for the year ended December 31, 2021, and for the year ended December 31, 2020, measurement period adjustments totaled an increase of approximately $2.1 million and related to the Company’s Communications segment. For the year ended December 31, 2022, fair value adjustments totaled a net decrease of approximately $1.2 million, and related primarily to the Company’s Communications segment. For the years ended December 31, 2021 and 2020, fair value adjustments across multiple segments totaled a net decrease of $29.5 million and net increase of $3.1 million, respectively, including a $2.8 million decrease and $1.0 million increase, respectively, related to mandatorily redeemable non-controlling interests. Earn-out payments totaled $37.8 million, $47.0 million and $50.4 million for the years ended December 31, 2022, 2021 and 2020, respectively. Equity Investments The Company’s equity investments as of December 31, 2022 include: (i) the Company’s 33% equity interests in Trans-Pecos Pipeline, LLC (“TPP”) and Comanche Trail Pipeline, LLC (“CTP,” and together with TPP, the “Waha JVs”); (ii) a 15% equity interest in Cross Country Infrastructure Services, Inc. (“CCI”); (iii) the Company’s 50% equity interests in each of FM Technology Holdings, LLC, FM USA Holdings, LLC and All Communications Solutions Holdings, LLC, collectively “FM Tech”; (iv) the Company’s interests in certain proportionately consolidated non-controlled contractual joint ventures; and (v) certain other equity investments. As of December 31, 2022 and 2021, the aggregate carrying value of the Company’s equity investments, including equity investments measured on an adjusted cost basis, totaled approximately $306 million and $267 million, respectively. As of both December 31, 2022 and 2021, equity investments measured on an adjusted cost basis, including the Company’s $15 million investment in CCI, totaled approximately $20 million. There were no impairments related to these investments in any of the years then ended. The Waha JVs. The Waha JVs own and operate certain pipeline infrastructure that transports natural gas to the Mexican border for export. The Company’s investments in the Waha JVs are accounted for as equity method investments. Equity in earnings related to the Company’s proportionate share of income from the Waha JVs, which is included within the Company’s Other segment, totaled approximately $30.2 million, $35.3 million and $31.3 million for the years ended December 31, 2022, 2021 and 2020, respectively. Distributions of earnings from the Waha JVs, which are included within operating cash flows, totaled $14.4 million, $7.7 million and $12.0 million for the years ended December 31, 2022, 2021 and 2020, respectively. Cumulative undistributed earnings from the Waha JVs, which represents cumulative equity in earnings for the Waha JVs less distributions of earnings, totaled $110.6 million as of December 31, 2022. The Company’s net investment in the Waha JVs, which differs from its proportionate share of the net assets of the Waha JVs due primarily to equity method goodwill associated with capitalized investment costs, totaled approximately $263 million and $216 million as of December 31, 2022 and 2021, respectively. The Waha JVs are party to separate non-recourse financing facilities, each of which are secured by pledges of the equity interests in the respective entities, as well as a first lien security interest over virtually all of their assets. The Waha JVs are also party to certain interest rate swaps (the “Waha JV swaps”), which are accounted for as qualifying cash flow hedges. The Company reflects its proportionate share of any unrealized fair market value gains or losses from fluctuations in interest rates associated with these swaps within other comprehensive income or loss, as appropriate. For the years ended December 31, 2022 and 2021, the Company’s proportionate share of unrecognized unrealized activity on the Waha JV swaps totaled gains of approximately $41.0 million and $18.2 million, respectively, or $30.9 million and $13.8 million, net of tax, respectively, and for the year ended December 31, 2020, totaled losses of approximately $24.4 million, or $18.5 million, net of tax. Other Investments. The Company has equity interests in certain telecommunications entities that are accounted for as equity method investments. As of December 31, 2022 and 2021, the Company had an aggregate investment of approximately $21 million and $20 million, respectively, in these entities, including $18 million and $17 million for FM Tech, respectively. The investment in FM Tech provides for additional funding upon the resolution of certain contingencies, of which $2 million was paid in 2021. The fair value of the remaining contingent payments for FM Tech, which are included within other current liabilities, was estimated to be $3 million as of both December 31, 2022 and 2021. As of December 31, 2022, the contingent payment could range up to $7 million. For the years ended December 31, 2022 and 2021, the Company made equity contributions related to its investments in telecommunications entities totaling approximately $1 million and $2 million, respectively, and for the year ended December 31, 2020, made no equity contributions. Equity in losses, net, related to the Company’s proportionate share of income from these telecommunications entities totaled approximately $0.3 million, $0.7 million and $1.5 million for the years ended December 31, 2022, 2021 and 2020, respectively. The difference between the carrying amount of these investments and the Company’s underlying equity in the net assets of the respective entities relates primarily to equity method goodwill associated with assembled workforce for each of these entities. Certain of these telecommunications entities provide services to MasTec. Expense recognized in connection with services provided by these entities totaled $7.6 million, $9.9 million and $11.5 million for the years ended December 31, 2022, 2021 and 2020, respectively. As of December 31, 2022 and 2021, related amounts payable to these entities totaled approximately $0.2 million and $0.3 million, respectively. In addition, the Company had an employee leasing arrangement with one of these entities and has advanced certain amounts to these entities. Employee lease expenses and advances to these entities totaled approximately $3.3 million, $0.2 million and $0.4 million for the years ended December 31, 2022, 2021 and 2020, respectively. As of December 31, 2022 and 2021, receivables related to these arrangements totaled $3.8 million and $0.9 million, respectively. The Company has 49% equity interests in certain entities included within its Communications and Power Delivery segments that are accounted for as equity method investments, for which its aggregate investment as of December 31, 2022 and 2021 totaled approximately $3 million and $4 million, respectively. For the year ended December 31, 2022, equity in losses,net, related to these entities totaled approximately $0.4 million, and there was no activity related to these entities for the year ended December 31, 2021. Certain of these entities provide construction services to MasTec. Expense recognized in connection with construction services provided by these entities totaled approximately $6.6 million for the year ended December 31, 2022 and related amounts payable were de minimis as of December 31, 2022. In addition, the Company has line of credit arrangements with these entities, which, as of December 31, 2022 and 2021, provide for up to $4.5 million and $8.5 million, respectively, of borrowing availability, of which $0.6 million and $0.4 million, respectively, was drawn, which amounts are included within other current assets in the consolidated balance sheets. In 2021, MasTec committed to fund up to $2.5 million for a 75% equity interest in Confluence Networks, LLC (“Confluence”), an undersea fiber-optic communications systems developer and VIE. As of December 31, 2022, a total of $1.9 million had been funded, of which $0.2 million and $1.7 million were funded during the years ended December 31, 2022 and 2021, respectively. Equity in losses related to the Company’s proportionate share of income from this investment totaled $0.4 million and $0.7 million for the years ended December 31, 2022 and 2021, respectively. MasTec has less than a majority of the members on the board of Confluence and does not have a controlling financial interest. As a result, management has determined that MasTec does not have the power to direct the primary activities that most significantly impact the economic performance of Confluence, nor is it the primary beneficiary. The Company does, however, have the ability to exert significant influence over Confluence as of December 31, 2022, and as a result, accounts for this investment as an equity method investment. The Company has certain equity investments in American Virtual Cloud Technologies, Inc. (“AVCT”), a company in which the Company currently has no active involvement. The Company’s investments in AVCT are included within other current assets in its consolidated financial statements, and include shares of AVCT common stock, which are equity securities, and warrants for the purchase of AVCT common stock, which are derivative financial instruments. Previously, the Company’s investment in AVCT included debentures that were convertible into shares of AVCT common stock, which were available-for-sale securities. In the third quarter of 2021, the Company’s investment in AVCT convertible debentures was automatically converted into shares of AVCT common stock. As of December 31, 2022 and 2021, the Company’s ownership interest in AVCT’s common stock totaled approximately 1% and 3%, respectively, and its aggregate ownership interest, assuming the exercise of all legally exercisable warrants into AVCT common stock, totaled approximately 1% and 6%, respectively. As of December 31, 2022 and 2021, the aggregate fair value of the Company’s investments in AVCT approximated $0.2 million and $7.9 million, respectively, with an aggregate cost approximating $6.3 million as of both periods. Unrealized fair value measurement activity related to the AVCT securities, which is recorded within other income or expense, as appropriate, totaled losses of approximately $7.7 million and $8.5 million for the years ended December 31, 2022 and 2021, respectively, and totaled gains of approximately $10.1 million for the year ended December 31, 2020. The fair value of the AVCT shares is determined based on the market price of identical securities, which is a Level 1 input, beginning as of the second quarter of 2021. Previously, the fair value of the shares was adjusted for certain restrictions on sale, a Level 3 input, which restrictions expired in April 2021. In the third quarter of 2021, in conjunction with the automatic conversion of the AVCT convertible debentures into shares of AVCT common stock, the Company reclassified a gain of $0.7 million from other comprehensive income to other income, net. Prior to the conversion of the AVCT convertible debentures in the third quarter of 2021, unrealized fair value measurement activity related to the AVCT convertible debentures, which were recognized within other comprehensive income, totaled losses of approximately $1.1 million, or $0.8 million, net of tax, for the year ended December 31, 2021, and totaled gains of approximately $1.8 million, or $1.4 million, net of tax, for the year ended December 31, 2020. The fair value of the AVCT convertible debentures was determined based on Level 3 inputs. Senior Notes As of both December 31, 2022 and 2021, the gross carrying amount of the Company’s 4.50% senior notes due August 15, 2028 (the “4.50% Senior Notes”) totaled $600.0 million and their estimated fair value totaled approximately $534.0 million and $619.5 million, for the respective periods. As of December 31, 2022, the gross carrying amount of the Company’s 6.625% senior notes due August 15, 2029 totaled $281.2 million, which notes are composed of $225.1 million aggregate principal amount of 6.625% IEA senior notes (the “6.625% IEA Senior Notes”) and $74.9 million aggregate principal amount of 6.625% MasTec senior notes (the “6.625% MasTec Senior Notes”), collectively, the “6.625% Senior Notes”). The estimated fair value of the 6.625% Senior Notes totaled approximately $280.5 million as of December 31, 2022. The estimated fair values of the Company’s 4.50% Senior Notes and, as of December 31, 2022, the Company’s 6.625% Senior Notes, was determined based on an exit price approach using Level 1 inputs. See Note 7 - Debt for information related to the Company’s debt instruments, including the assumption of IEA’s 6.625% senior notes and the related debt exchange transaction.

Acquisition-related contingent consideration and other liabilities is composed of Earn-outs, which represent the estimated fair value of future amounts payable for businesses, including for mandatorily redeemable non-controlling interests, that are contingent upon the acquired business achieving certain levels of earnings in the future. As of December 31, 2022 and 2021, the estimated fair value of the Company’s Earn-out liabilities totaled $127.4 million and $160.2 million, respectively, of which $13.9 million related to mandatorily redeemable non-controlling interests as of both periods. Earn-out liabilities included within other current liabilities totaled approximately $37.7 million and $38.8 million as of December 31, 2022 and 2021, respectively. The fair values of the Company’s Earn-out liabilities are estimated using income approaches such as discounted cash flows or option pricing models, both of which incorporate significant inputs not observable in the market (Level 3 inputs), including management’s estimates and entity-specific assumptions, and are evaluated on an ongoing basis. Key assumptions include the discount rate, which was 12.0% as of December 31, 2022, and probability-weighted projections of earnings before interest, taxes, depreciation and amortization (“EBITDA”). Significant changes in any of these assumptions could result in significantly higher or lower potential Earn-out liabilities. The ultimate payment amounts for the Company’s Earn-out liabilities will be determined based on the actual results achieved by the acquired businesses. As of December 31, 2022, the range of potential undiscounted Earn-out liabilities was estimated to be between $38 million and $144 million; however, there is no maximum payment amount.

Earn-out activity consists primarily of additions from new business combinations; changes in the expected fair value of future payment obligations; and payments. For the years ended December 31, 2022, 2021 and 2020, additions from new business combinations totaled approximately $2.8 million, $101.6 million and $7.2 million, respectively. Measurement period adjustments for the year ended December 31, 2022 totaled an increase, net, of approximately $3.3 million and related to a net increase in the Company’s Oil and Gas segment, partially offset by a decrease in its Communications segment. There were no measurement period adjustments for the year ended December 31, 2021, and for the year ended December 31, 2020, measurement period adjustments totaled an increase of approximately $2.1 million and related to the Company’s Communications segment. For the year ended December 31, 2022, fair value adjustments totaled a net decrease of approximately $1.2 million, and related primarily to the Company’s Communications segment. For the years ended December 31, 2021 and 2020, fair value adjustments across multiple segments totaled a net decrease of $29.5 million and net increase of $3.1 million, respectively, including a $2.8 million decrease and $1.0 million increase, respectively, related to mandatorily redeemable non-controlling interests. Earn-out payments totaled $37.8 million, $47.0 million and $50.4 million for the years ended December 31, 2022, 2021 and 2020, respectively.

The Company’s equity investments as of December 31, 2022 include: (i) the Company’s 33% equity interests in Trans-Pecos Pipeline, LLC (“TPP”) and Comanche Trail Pipeline, LLC (“CTP,” and together with TPP, the “Waha JVs”); (ii) a 15% equity interest in Cross Country Infrastructure Services, Inc. (“CCI”); (iii) the Company’s 50% equity interests in each of FM Technology Holdings, LLC, FM USA Holdings, LLC and All Communications Solutions Holdings, LLC, collectively “FM Tech”; (iv) the Company’s interests in certain proportionately consolidated

As of December 31, 2022 and 2021, the aggregate carrying value of the Company’s equity investments, including equity investments measured on an adjusted cost basis, totaled approximately $306 million and $267 million, respectively. As of both December 31, 2022 and 2021, equity investments measured on an adjusted cost basis, including the Company’s $15 million investment in CCI, totaled approximately $20 million. There were no impairments related to these investments in any of the years then ended.

The Waha JVs. The Waha JVs own and operate certain pipeline infrastructure that transports natural gas to the Mexican border for export. The Company’s investments in the Waha JVs are accounted for as equity method investments. Equity in earnings related to the Company’s proportionate share of income from the Waha JVs, which is included within the Company’s Other segment, totaled approximately $30.2 million, $35.3 million and $31.3 million for the years ended December 31, 2022, 2021 and 2020, respectively. Distributions of earnings from the Waha JVs, which are included within operating cash flows, totaled $14.4 million, $7.7 million and $12.0 million for the years ended December 31, 2022, 2021 and 2020, respectively. Cumulative undistributed earnings from the Waha JVs, which represents cumulative equity in earnings for the Waha JVs less distributions of earnings, totaled $110.6 million as of December 31, 2022. The Company’s net investment in the Waha JVs, which differs from its proportionate share of the net assets of the Waha JVs due primarily to equity method goodwill associated with capitalized investment costs, totaled approximately $263 million and $216 million as of December 31, 2022 and 2021, respectively.

The Waha JVs are party to separate non-recourse financing facilities, each of which are secured by pledges of the equity interests in the respective entities, as well as a first lien security interest over virtually all of their assets. The Waha JVs are also party to certain interest rate swaps (the “Waha JV swaps”), which are accounted for as qualifying cash flow hedges. The Company reflects its proportionate share of any unrealized fair market value gains or losses from fluctuations in interest rates associated with these swaps within other comprehensive income or loss, as appropriate. For the years ended December 31, 2022 and 2021, the Company’s proportionate share of unrecognized unrealized activity on the Waha JV swaps totaled gains of approximately $41.0 million and $18.2 million, respectively, or $30.9 million and $13.8 million, net of tax, respectively, and for the year ended December 31, 2020, totaled losses of approximately $24.4 million, or $18.5 million, net of tax.

Other Investments. The Company has equity interests in certain telecommunications entities that are accounted for as equity method investments. As of December 31, 2022 and 2021, the Company had an aggregate investment of approximately $21 million and $20 million, respectively, in these entities, including $18 million and $17 million for FM Tech, respectively. The investment in FM Tech provides for additional funding upon the resolution of certain contingencies, of which $2 million was paid in 2021. The fair value of the remaining contingent payments for FM Tech, which are included within other current liabilities, was estimated to be $3 million as of both December 31, 2022 and 2021. As of December 31, 2022, the contingent payment could range up to $7 million. For the years ended December 31, 2022 and 2021, the Company made equity contributions related to its investments in telecommunications entities totaling approximately $1 million and $2 million, respectively, and for the year ended December 31, 2020, made no equity contributions. Equity in losses, net, related to the Company’s proportionate share of income from these telecommunications entities totaled approximately $0.3 million, $0.7 million and $1.5 million for the years ended December 31, 2022, 2021 and 2020, respectively. The difference between the carrying amount of these investments and the Company’s underlying equity in the net assets of the respective entities relates primarily to equity method goodwill associated with assembled workforce for each of these entities.

Certain of these telecommunications entities provide services to MasTec. Expense recognized in connection with services provided by these entities totaled $7.6 million, $9.9 million and $11.5 million for the years ended December 31, 2022, 2021 and 2020, respectively. As of December 31, 2022 and 2021, related amounts payable to these entities totaled approximately $0.2 million and $0.3 million, respectively. In addition, the Company had an employee leasing arrangement with one of these entities and has advanced certain amounts to these entities. Employee lease expenses and advances to these entities totaled approximately $3.3 million, $0.2 million and $0.4 million for the years ended December 31, 2022, 2021 and 2020, respectively. As of December 31, 2022 and 2021, receivables related to these arrangements totaled $3.8 million and $0.9 million, respectively.

The Company has 49% equity interests in certain entities included within its Communications and Power Delivery segments that are accounted for as equity method investments, for which its aggregate investment as of December 31, 2022 and 2021 totaled approximately $3 million and $4 million, respectively. For the year ended December 31, 2022, equity in losses,net, related to these entities totaled approximately $0.4 million, and there was no activity related to these entities for the year ended December 31, 2021. Certain of these entities provide construction services to MasTec. Expense recognized in connection with construction services provided by these entities totaled approximately $6.6 million for the year ended December 31, 2022 and related amounts payable were de minimis as of December 31, 2022. In addition, the Company has line of credit arrangements with these entities, which, as of December 31, 2022 and 2021, provide for up to $4.5 million and $8.5 million, respectively, of borrowing availability, of which $0.6 million and $0.4 million, respectively, was drawn, which amounts are included within other current assets in the consolidated balance sheets.

In 2021, MasTec committed to fund up to $2.5 million for a 75% equity interest in Confluence Networks, LLC (“Confluence”), an undersea fiber-optic communications systems developer and VIE. As of December 31, 2022, a total of $1.9 million had been funded, of which $0.2 million and $1.7 million were funded during the years ended December 31, 2022 and 2021, respectively. Equity in losses related to the Company’s proportionate share of income from this investment totaled $0.4 million and $0.7 million for the years ended December 31, 2022 and 2021, respectively. MasTec has less than a majority of the members on the board of Confluence and does not have a controlling financial interest. As a result, management has determined that MasTec does not have the power to direct the primary activities that most significantly impact the economic performance of Confluence, nor is it the primary beneficiary. The Company does, however, have the ability to exert significant influence over Confluence as of December 31, 2022, and as a result, accounts for this investment as an equity method investment.

The Company has certain equity investments in American Virtual Cloud Technologies, Inc. (“AVCT”), a company in which the Company currently has no active involvement. The Company’s investments in AVCT are included within other current assets in its consolidated financial statements, and include shares of AVCT common stock, which are equity securities, and warrants for the purchase of AVCT common stock, which are derivative financial instruments. Previously, the Company’s investment in AVCT included debentures that were convertible into shares of AVCT common stock, which were available-for-sale securities. In the third quarter of 2021, the Company’s investment in AVCT convertible debentures

was automatically converted into shares of AVCT common stock. As of December 31, 2022 and 2021, the Company’s ownership interest in AVCT’s common stock totaled approximately 1% and 3%, respectively, and its aggregate ownership interest, assuming the exercise of all legally exercisable warrants into AVCT common stock, totaled approximately 1% and 6%, respectively.

As of December 31, 2022 and 2021, the aggregate fair value of the Company’s investments in AVCT approximated $0.2 million and $7.9 million, respectively, with an aggregate cost approximating $6.3 million as of both periods. Unrealized fair value measurement activity related to the AVCT securities, which is recorded within other income or expense, as appropriate, totaled losses of approximately $7.7 million and $8.5 million for the years ended December 31, 2022 and 2021, respectively, and totaled gains of approximately $10.1 million for the year ended December 31, 2020. The fair value of the AVCT shares is determined based on the market price of identical securities, which is a Level 1 input, beginning as of the second quarter of 2021. Previously, the fair value of the shares was adjusted for certain restrictions on sale, a Level 3 input, which restrictions expired in April 2021. In the third quarter of 2021, in conjunction with the automatic conversion of the AVCT convertible debentures into shares of AVCT common stock, the Company reclassified a gain of $0.7 million from other comprehensive income to other income, net. Prior to the conversion of the AVCT convertible debentures in the third quarter of 2021, unrealized fair value measurement activity related to the AVCT convertible debentures, which were recognized within other comprehensive income, totaled losses of approximately $1.1 million, or $0.8 million, net of tax, for the year ended December 31, 2021, and totaled gains of approximately $1.8 million, or $1.4 million, net of tax, for the year ended December 31, 2020. The fair value of the AVCT convertible debentures was determined based on Level 3 inputs.

As of both December 31, 2022 and 2021, the gross carrying amount of the Company’s 4.50% senior notes due August 15, 2028 (the “4.50% Senior Notes”) totaled $600.0 million and their estimated fair value totaled approximately $534.0 million and $619.5 million, for the respective periods. As of December 31, 2022, the gross carrying amount of the Company’s 6.625% senior notes due August 15, 2029 totaled $281.2 million, which notes are composed of $225.1 million aggregate principal amount of 6.625% IEA senior notes (the “6.625% IEA Senior Notes”) and $74.9 million aggregate principal amount of 6.625% MasTec senior notes (the “6.625% MasTec Senior Notes”), collectively, the “6.625% Senior Notes”). The estimated fair value of the 6.625% Senior Notes totaled approximately $280.5 million as of December 31, 2022. The estimated fair values of the Company’s 4.50% Senior Notes and, as of December 31, 2022, the Company’s 6.625% Senior Notes, was determined based on an exit price approach using Level 1 inputs. See Note 7 - Debt for information related to the Company’s debt instruments, including the assumption of IEA’s 6.625% senior notes and the related debt exchange transaction.